Positioning of Chest and Positioning Situations/Errors

Question 1

why is a PA chest preferred to an AP projection?

Answer 1

reduces magnification of heart

Question 2

Why should a left lateral be performed unless departmental protocol indicates otherwise?

Answer 2

better demonstrates the heart region

Question 3

The CR is placed at what level of vertebra for a PA chest projection?

Answer 3

T7

Question 4

How much separation of the posterior ribs on a lateral chest projection indicates excessive rotation from a true lateral position?

Answer 4

0.5 to 0.75 inch

Question 5

To prevent the clavicles from obscuring the apices on an AP projection of the chest, the CR should be angled __________ so that it is perpendicular to the ___________.

Answer 5

caudad; sternum

Question 6

What position would be used if a patient were unable to stand but the physician suspected that the patient had fluid in the left lung?

Answer 6

left lateral decubitus

Question 7

What specific position would be used if the patient were unable to stand but the physician suspected that the patient had free air in the left pleural cavity?

Answer 7

right lateral decubitus

Question 8

What circumstances or clinical indications suggest that an AP lordotic projection should be ordered?

Answer 8

rule out calcifications beneath the clavicles

Question 9

What position/projection would be used for a patient who is too ill or weak to stand for an AP lordotic projection?

Answer 9

AP semiaxial projection, CR 15-20 degrees cephalad

Question 10

Which anterior oblique projection would best elongate the left thorax?

Answer 10

RAO

Question 11

Which posterior oblique would best elongate the left thorax?

Answer 11

LPO

Question 12

For certain studies of the heart, which oblique projection requires a rotation of 60 degrees?

Answer 12

LAO

Question 13

Where is the CR placed for a lateral projection of the upper airway?

Answer 13

C6 or C7, midway between thyroid cartilage and jugular notch

Question 14

Careful collimation during a chest radiograph will improve image quality by decreasing what to the IR?

Answer 14

scatter radiation

Question 15

What is the recommended patient instruction when performing an erect PA chest on a female patient with large breasts?

Answer 15

lift breast up and outward then remove hands as she leans against IR to keep in position

Question 16

T/F: No lead shielding is necessary for male patients or women older than age 65 during radiographic imaging of the chest.

Answer 16

false

Question 17

An erect chest PA radiograph aids the patient to achieve full inspiration and helps to prevent __________________ and ________________ of the pulmonary vessels.

Answer 17

engorgement; hyperemia

Question 18

T/F: a grid is not recommended for an LPO projection of the adult chest.

Answer 18

false

Question 19

A radiograph of a PA view of the chest shows that the sternoclavicular (SC) joints are not the same distance from the spine. The right SC joint is closer to the midline than the left SC joint. What is the positioning error?

Answer 19

rotation

patient is slightly rotated into an RAO position

Question 20

A radiograph of a PA projection of the chest demonstrates only 7 posterior ribs above the diaphragm. What caused this problem and how could it be prevented on the repeat exposures?

Answer 20

lungs are underinflated

take exposure on the 2nd inspiration

Question 21

A radiograph of a PA projection of the chest demonstrates the top of the apices is cut off and a wide collimation border can be seen below the diaphragm. How can this be corrected during the repeat radiograph?

Answer 21

make sure CR is lined up with T7 vertebra and that the IR is centered with the CR

Question 22

A patient comes for a presurgical chest examination. The clinical history indicates a possible situs inversus of the thorax (transposition of structures within thorax). Which positioning action must be taken to perform a successful examination?

Answer 22

make sure the correct anatomic marker is placed correctly

Question 23

A radiograph of a lateral projection of the chest shows the posterior ribs and costophrenic angles are separated more than 1” or 2.5 cm, indicating excessive rotation. Describe a possible method for determining the direction of rotation.

Answer 23

determine which hemidiaphragm is more posterior or anterior

Question 24

A patient enters the emergency room with a possible hemothorax in the right lung caused by a MVA. The patient is unable to stand or sit erect. Which specific projection would best demonstrate this condition, and why?

Answer 24

right lateral decubitus bc the side of interest should be down

Question 25

A young child enters ER with a possible foreign body in one of the bronchi of the lung. The peanut cannot be seen on the PA and lateral projections. Which additional projection(s) could the technologist perform to locate the foreign body?

Answer 25

AP and lateral upper airway

Question 26

A routine chest series indicates a possible mass beneath the patient’s right clavicle. PA and lateral are in conclusive. What additional could be taken?

Answer 26

AP lordotic

Question 27

PA and left lateral projections demonstrate a suspicious region in the left lung. The radiologist orders an oblique projection that will best demonstrate the left thorax. Which specific oblique projections will best elongate the left thorax?

Answer 27

LPO and RAO